Lithium battery, lithium battery module, and electronic device

Abstract

A lithium battery module includes: a wound body formed by winding a positive electrode and a negative electrode with a separator interposed between the positive electrode and the negative electrode; an exterior body enclosing the wound body; a protective case housing the exterior body; and a pressing member provided between the exterior body and the protective case, in which the exterior body includes: a first member serving as a base; and a second member provided in a partial region of the exterior body, the second member has lower stretchability than the first member, and the pressing member transfers pressing force from the protective case to the wound body through the second member to fix the wound body by pressing force from the exterior body.

What is claimed is: 
     
       1. A lithium battery module comprising:
 a wound body formed by winding a positive electrode and a negative electrode with a separator interposed between the positive electrode and the negative electrode; 
 an exterior body enclosing the wound body; 
 a protective case housing the exterior body; and 
 a pressing member provided between the exterior body and the protective case, 
 wherein: 
 the exterior body includes:
 a first member serving as a base; and 
 a second member provided in a partial region of the exterior body, 
 
 the second member has a lower stretchability than the first member, 
 the pressing member contacts with the second member and transfers a pressing force from the protective case to the wound body through the second member to fix the wound body by a pressing force from the exterior body, and 
 an area of the partial region in which the second member is provided is larger than a contact area between the second member and the pressing member. 
 
     
     
       2. The lithium battery module according to  claim 1 , wherein the second member is provided in such a manner as to be fitted in the partial region of the exterior body. 
     
     
       3. The lithium battery module according to  claim 1 , wherein the second member is provided by being bonded from an outside of the exterior body to the partial region of the exterior body. 
     
     
       4. The lithium battery module according to  claim 1 , wherein the pressing member transmits a pressing force generated when the exterior body expands to the wound body through the second member. 
     
     
       5. The lithium battery module according to  claim 1 , wherein:
 the exterior body has a flat shape having a pair of flat surfaces, 
 the second member is provided on each of the pair of flat surfaces in such a manner that the second member provided on one flat surface overlaps the second member provided on the other flat surface, and 
 the pressing member includes:
 a first pressing member corresponding to the second member provided on the one flat surface; and 
 a second pressing member corresponding to the second member provided on the other flat surface. 
 
 
     
     
       6. The lithium battery module according to  claim 1 , wherein the pressing member is disposed in such a manner as to form a space between the protective case and the exterior body and on both sides of the pressing member when the pressing member is sandwiched between the protective case and the second member. 
     
     
       7. The lithium battery module according to  claim 1 , wherein a thickness of the second member is greater than a thickness of the first member such that the pressing member is prevented from being in contact with a region of the first member of the exterior body when the pressing member is sandwiched between the protective case and the second member. 
     
     
       8. The lithium battery module according to  claim 1 , wherein the second member and the pressing member are cylindrical. 
     
     
       9. The lithium battery module according to  claim 5 , wherein the second member is provided at a center portion of the each of the pair of flat surfaces of the exterior body. 
     
     
       10. The lithium battery module according to  claim 1 , wherein the second member comprises a plate material made of resin, glass, or ceramic. 
     
     
       11. An electronic device comprising a casing housing the lithium battery module according to  claim 2 . 
     
     
       12. An electronic device comprising a casing capable of mounting the lithium battery module according to  claim 2 . 
     
     
       13. An electronic device comprising:
 a lithium battery module; and 
 a casing housing the lithium battery module, 
 the lithium battery module comprising:
 a wound body formed by a positive electrode and a negative electrode with a separator interposed between the positive electrode and the negative electrode; 
 an exterior body enclosing the wound body, the exterior body including (i) a first member serving as a base, and (ii) a second member having less stretchability than the first member; 
 a protective case housing the exterior body; and 
 a pressing member provided between the exterior body and the protective case, 
 
 wherein: 
 the pressing member contacts with the second member and transfers a pressing force from the protective case to the wound body through the second member to fix the wound body by a pressing force from the exterior body, and 
 an area of a partial region of the exterior body in which the second member is provided is larger than a contact area between the second member and the pressing member.